How to Delete a Primary Key Index in Oracle

Deleting a primary key index can be a complex task, as it involves modifying the structure of the database table. Here are the steps you can follow to delete a primary key index:

Identify the name of the primary key index: 

SELECT index_name FROM dba_constraints WHERE table_name = 'table_name' AND constraint_type = 'P';

Drop the primary key constraint: Before you can drop the primary key index, you must first drop the primary key constraint. 
ALTER TABLE table_name DROP PRIMARY KEY;

Drop the primary key index: Once the primary key constraint has been dropped, you can then drop the primary key index

DROP INDEX index_name ON table_name;

It's important to note that deleting a primary key index will also remove the associated primary key constraint, which can have implications for data integrity and referential integrity in your database. Be sure to fully understand the implications of removing a primary key index before proceeding.